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PAROTID REGION. 
which arise from it, and passes down between 
the styloid process and the pterygoid muscles, 
so as to come in contact with the pharynx and 
the internal carotid artery, as well as the in- 
ternal jugular vein, and the eighth, ninth, and 
sympathetic nerves. A portion of the gland 
passes with the internal maxillary artery be- 
tween the ramus of the jaw and the internal 
lateral ligament; it here comes into contact 
with the inferior maxillary nerve, and some- 
times reaches the space between the external 
and internal pterygoid muscles. 
In addition to the relations here pointed out 
to the parts by which it is surrounded and 
limited, the parotid has important relations to 
vessels and nerves which pass through its sub- 
stance or are deeply imbedded within and 
beneath it. 
Arteries.—The external carotid artery passes 
into the lower border of the gland near its 
deep surface; as it ascends it becomes more 
superficial, and is continued upwards under 
the name of the superficial temporal, which 
passes up between the ear and the articulation 
of the jaw, crosses over the zygoma, and so 
emerges from beneath the parotid gland and its 
ia. 
The internal mazillary artery passes off 
from the carotid at right angles. At its origin 
it is imbedded in the substance of the parotid, 
and is nearly on a level with the lower extre- 
mity of the lobe of the ear; it bends down- 
wards and inwards, and escapes from the pa- 
rotid by passing between the ramus of the jaw 
and its internal lateral ligament. 
The transversalis faciei arises from the ca- 
rotid or from the superficial temporal artery at 
a variable distance between the angle and neck 
Its origin is imbedded in the 
substance of the parotid; it then goes upwards 
and forwards, and passes out beneath the ante- 
rior border of the gland, lying between it and 
the masseter muscle. 
The posterior auricular artery is a small 
branch of uncertain origin. When regular it 
arises from the external carotid, above the di- 
gastric and stylo-hyoid muscles, opposite the 
point of the styloid process; it is here partly 
concealed by the parotid gland, in the posterior 
part of which it is imbedded ; it then passes 
upwards and backwards between the ear and 
the mastoid process. While this artery is im- 
bedded in the parotid it sends off a small 
stylo-mastoid branch, which passes upwards 
to enter the stylo-mastoid foramen. In ad- 
dition to the above-mentioned arteries there 
are several branches variable in their number, 
size, and situation, which pass off from the 
carotid and its branches and are distributed to 
the substance of the parotid gland. 
Veins.—The veins corresponding to the ter- 
minal branches of the external carotid artery 
accompany the arteries and are consequently 
imbedded in the parotid gland. The temporal 
_ and internal maxillary veins unite and form a 
common trunk, which lies superficial to the 
external carotid artery. This common trunk 
receives the posterior auricular and the trans- 
verse facial veins, as well as some veins from 
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the substance of the parotid, and so the com- 
mencement of the external jugular vein is 
formed. There is also a communicating branch 
which passes through the parotid gland from 
the internal to-the external jugular vein ; this 
branch may be looked upon as one of the 
origins, and in some cases it is the chief origin 
of the external jugular vein. 
Nerves.—We have next to study the rela- 
tions of the nerves which are found in the 
parotid region. 
The nerve which lies most superficially in 
this region is the great auricular, some small 
branches of which lie superficial to the parotid 
fascia and are distributed to the skin of the 
parotid region, while other branches pierce the 
fascia, and pass through the parotid ina di- 
rection forwards and upwards to be distributed 
on the skin of the cheek. The nerve then 
sends off two branches, the superficial auri- 
cular and the deep auricular. 
The superficial auricular branch of the great 
auricular nerve passing vertically upwards in 
the dense fibrous tissue which connects the 
parotid with the skin, reaches the inferior part 
of the concha, and is distributed to the skin of 
the ear. 
The deep auricular branch passes through 
the substance of the parotid, to place itself in 
front of the mastoid process, crossing at an 
acute angle the auricular branch of the facial 
nerve, which is deeper than it, and with which 
it anastomoses by a branch of considerable size, 
The nerve then passes backwards and divides 
into branches which are distributed to the ex- 
ternal ear, and to the skin over the occipital 
region. 
The auriculo-temporal nerve arises from the 
trunk of the superior maxillary by two por- 
tions, between which passes occasionally the 
middle meningeal artery. It passes backwards 
beneath the external pterygoid muscle, and 
between the internal lateral ligament and neck 
of the jaw; it then divides into two branches, 
a superficial or temporal and a deep or auri- 
cular branch. The superficial temporal passes 
up between the ear and the articulation of the 
jaw, crossing the root of the zygoma, and be- 
coming superficial above the parotid gland ; it 
then supplies the skin of the temple and side 
of the head. In its course this nerve sends off 
one or two branches which communicate with 
the portio dura nerve; it also sends branches to 
the tempero-maxillary articulation and to the 
external auditory meatus. The auricular branch 
forms a plexus behind the neck of the jaw and 
around the internal maxillary artery; it then 
divides into several branches, some of which 
pass through the parotid to be distributed on 
the external ear, while others anastomose with 
branches of the cervical plexus, particularly 
with the great auricular nerve. One branch 
joins the dental nerve just before it enters the 
_ dental canal, and another passes into the tem- 
pero-maxillary articulation. 
The portio dura nerve passes out of the 
stylo-mastoid foramen and enters the substance 
of the parotid gland. At its exit from the 
foramen the nerve sends off three small branches, 
